基于波动方程的上下缆地震数据鬼波压制方法研究  

The study of a deghosting method of over/under streamer seismic data based on wave equation

作　　者：管西竹[1] 陈宝书 符力耘[1] 陶杰 李列 

机构地区：[1]中国科学院油气资源研究重点实验室,中国科学院地质与地球物理研究所,北京100029 [2]中海油研究总院,北京100027 [3]中海石油(中国)有限公司湛江分公司,广东湛江524057

出　　处：《地球物理学报》2015年第10期3746-3757,共12页Chinese Journal of Geophysics

基　　金：国家自然科学基金项目(41130418,40925013);国家科技重大专项(2011ZX05025-001-02)联合资助

摘　　要：本文发展基于波动方程的上下缆鬼波压制方法,推导了上下缆地震波场频率波数域波动方程延拓合并公式.基于Fourier变换的波场解析延拓确保上下缆资料振幅相位的一致性,消除了长拖缆远偏移距信号的计算误差,同时具有较高的计算效率;上下缆地震波场的波动方程法合并有效解偶鬼波干涉,实现综合利用上下缆地震数据压制鬼波.理论模型数据和实际采集地震数据的测试表明了方法的有效性.In marine seismic acquisition,ghost effect due to the strong reflection of the sea surface causes serious notch trap in the spectrum.Ghost effect can be reduced by over/under towed streamer acquisition.However,most of deghosting technology for over/under streamer acquisition is based on seismic kinematics method,which cannot effectively solve the ghost wave interference and brings incomplete ghost suppression and distortion of the effective signal.It is necessary to develop the deghosting technology for over/under streamer.Cases studies of synthetic and real seismic data sets demonstrate that our seismic wavefield extrapolation based on Fourier transform ensures the consistency of the seismic amplitude and phase of over/under streamer seismic data and significantly eliminates the amplitude and phase error of far offset especially for the long streamer condition,which helps to decouple the real wave and the ghost wave and fill notch effect in the spectrum.In order to take advantage of both shallow and deep streamers,it has been proposed to record the pressure field at two different depths and to combine optimally all the measurements.We propose adeghosting method of over/under streamer based on seismic wave equation continuation formula in the frequency wavenumber domain,which eliminate far offset signal calculation error of the long streamer contract to the traditional dephase and sum algorithm.Theanalytical seismic wave continuation based on Fourier transform ensure the consistency of the amplitude and phase of seismic signal from over/under streamer seismic acquisition with high computing efficiency,suppress the ghost signal that interference the up-going signal from the earth under water effectively and fill the notchesin the amplitude spectrum.A synthetic single shot gather is used to verify the performance of the proposed method.Finally,we apply the proposed method on a real over/undermarine data set from China.The results show that the proposed method can simultaneously achieve good imaging of shallow and d

关 键 词：海上地震采集 上下缆 鬼波压制 波动方程延拓合并 频率波数域 

分 类 号：P631[天文地球—地质矿产勘探]